Meta-analyses have become the gold standard for synthesizing evidence from multiple clinical trials, and they are especially useful when outcomes are rare or adverse since individual trials often lack sufficient power to detect a treatment effect. However, when zero events are observed in one or both treatment arms in a trial, commonly used…

Background The CLUSTER model of searching was proposed as a systematic method of searching for studies for reviews of complex interventions. Aim: The method has not been evaluated before. This methodological review identified and evaluated a sample of evidence syntheses that have used CLUSTER. Methods: A forward citation search on the seed CLUSTER…

During drug development, evidence can emerge to suggest a treatment is more effective in a specific patient subgroup. Whilst early trials may be conducted in biomarker-mixed populations, later trials are more likely to enroll biomarker-positive patients alone, thus leading to trials of the same treatment investigated in different populations. When…

In Bayesian random-effects meta-analysis, the use of weakly informative prior distributions is of particular benefit in cases where only a few studies are included, a situation often encountered in health technology assessment (HTA). Suggestions for empirical prior distributions are available in the literature but it is unknown whether these are…

Risk of bias (RoB) assessments are a core element of evidence synthesis but can be time consuming and subjective. We aimed to develop a decision rule-based algorithm for RoB assessment of seroprevalence studies. We developed the SeroTracker-RoB algorithm. The algorithm derives seven objective and two subjective critical appraisal items from the…

The exponential increase in published articles makes a thorough and expedient review of literature increasingly challenging. This review delineated automated tools and platforms that employ artificial intelligence (AI) approaches and evaluated the reported benefits and challenges in using such methods. A search was conducted in 4 databases…

In evidence-based practice, new topics generally only have a few studies available for synthesis. As a result, the evidence of such meta-analyses raised substantial concerns. We investigated the robustness of the evidence from these earliest studies. Real-world data from the Cochrane Database of Systematic Reviews (CDSR) were collected. We…

Reviewing complex interventions is challenging because they include many elements that can interact dynamically in a nonlinear manner. A systems perspective offers a way of thinking to help understand complex issues, but its application in evidence synthesis is not established. The aim of this project was to understand how and why systems…

The short time frame associated with rapid reviews can be challenging for researchers conducting qualitative evidence synthesis. In these circumstances a Best-Fit Framework Synthesis, drawing upon existing theory and/or research, may be conducted to rapidly make sense of qualitative evidence. This article discusses a "Rapid Best-Fit"…

Background: It is challenging to keep systematic reviews (SR) current and updated. Cochrane designated some of its SRs as "stable," that is, not in need of updating. The issue of stabilizing an SR is an important in research synthesis, because it could help reduce research waste. The aim of this study was to analyze publicly available…

In fields (such as population health) where randomised trials are often lacking, systematic reviews (SRs) can harness diversity in study design, settings and populations to assess the evidence for a putative causal relationship. SRs may incorporate causal assessment approaches (CAAs), sometimes called 'causal reviews', but there is currently no…

Randomised controlled trials of cancer treatments typically report progression free survival (PFS) and overall survival (OS) outcomes. Existing methods to synthesise evidence on PFS and OS either rely on the proportional hazards assumption or make parametric assumptions which may not capture the diverse survival curve shapes across studies and…

Background: Systematic reviews cataloguing the barriers to and facilitators of various outcomes are increasingly popular, despite criticisms of this type of review on philosophical, methodological, and practical grounds. The aims of this review are to appraise, analyze, and discuss the reporting and synthesis practices used in recently published…

The Cochrane COVID-19 Study Register (CCSR) is a public, continually updated database of COVID-19 study references. The aim of this study-based register is to support rapid and living evidence synthesis, including an evidence ecosystem of COVID-19 research (CEOsys). In November and December 2020, we conducted an evaluation of the CCSR for CEOsys,…

Background: Evidence syntheses provide the basis for evidence-based decision making in healthcare. To judge the certainty of findings for the specific decision context evidence syntheses should consider context suitability (ie, generalizability, external validity, applicability or transferability). Our objective was to determine the status quo and…